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Purple Loosestrife is a tall, showy plant found in several areas of Weber County. Some of the weed infestations can be treated with herbicides quite easily. Not so with the Purple Loosestrife population along the Weber River as it flows west from the bridge at 1900 West and further west and north in our marshlands. The use of most types of chemicals along a waterway would be unwise - but the biggest challenge with this particular infestation is the lack of accessibility to it. It is nearly impossible to direct herbicide on the weeds found here.
weed

In 1993, Purple Loosestrife was first identified in Weber County. At about the same time, we learned of the damage this alien species can cause in wetland habitat. A grant for $200.00 was obtained from Partners for Wildlife as a result of the sightings of Purple Loosestrife along some drainage and irrigation ditches in the northwestern part of the County. The following year, armed with backpack sprayers and herbicide, all known infestations were treated. We were concerned, however, that the weed may already have a foothold somewhere downstream.

An Aerial Survey was flown in 1994 to look for the purple invader in the Salt Creek area, south of Willard Bay and west of Plain City. What appeared to be a few acres of purple loosestrife were found and hastily charted. A follow-up expedition on foot yielded only insect bites and wet feet, but we continued the search and found a handful of vigorous plants in the Weber River at the 1900 West bridge.

In 1995, the Weed Supervisor and the Extension Agent set out on a float expedition down the Weber River. To the surprise of the crew, Purple Loosestrife was found along the riverbanks and in dry flood channels for most of length of the river between 1900 West and 4700 West.

The Big Adventure of the day was the discovery of a 6 foot high irrigation diversion dam spanning the river by Plain City. The roar of the water over the concrete and rocks was alarming in the distance. The boat was beached and options considered. An escaping flow of water over some rock fill was chosen over portage and the survey trip was completed with only a few gallons of water taken over the stern. The expanse of the Purple Loosestrife infestation was a bit discouraging. It was obvious that we were not going to be successful at eradicating it at that time with herbacides, and that we should investigate alternative methods of supression. Biological control is now the preferred method of controlling Purple Loosestrife.